Drafting a Contract Worker Employment Letter: What Clauses Should I Include or Exclude?

I was instructed to draft a letter of employment for a contract worker for my company. I would appreciate it if members could provide some input on what appropriate clauses I should include/exclude to differentiate between permanent workers. Thank you.

If you intend to draft a letter of offer for a definite period of work, then the usual offer letter is sufficient. However, include the following clause:

"This offer of employment is for a period of ____ years from __ to __ (dates), and as such, your service will be terminated automatically on completion of the aforesaid period."

"This offer of employment is purely for the work specified, and your service will automatically be terminated on completion of the specified work."

Regards,
Madhu.T.K